When you are creating skin tones, you must remember this important rule:
Pigment Tattooed + Skin Tone = Final Color
Skin tones have base colors and can be placed on a color wheel just like all colors. Below is a color wheel illustrative of the where different skin tones are found on a color wheel. This information, combined with the base color of the pigment selected for camouflage, creates the final healed result.

COMMON FORMULAE FOR CAMOUFLAGE:
For Caucasian Skin Caucasian Skin
For all other skin types, excluding women of color, always start with "Caucasian Skin".
For Light Olive Skin use a combination of Caucasian Skin and Blonde.
For Darker Olive Skin use a combination of Caucasian Skin and Chestnut.
For Facelift Scars behind the ears, neck and ruddier areas: Caucasian Skin and Breast Rouge, percentage depending on the amount of red/violet in the surrounding skin.
For shadowing under nipples: straight Blonde